int prime(int n) {
    if(n==2)return 1;
    if(n<2||n%2==0)return 0;
    int c;
    for(c=3; c*c<=n; c+=2)
        if(n%c==0)
            return 0;
    return 1;
}
int prime2(int n) {
    int c;
    for(c=2; c*c<=n; c++)
        if(n%c==0)
            return 0;
    return 1;
}
int main() {
    long long start=clock();
    int n,p,q;
    for(n=6; n<=2000000; n+=2) {
        int find=0;
        for(p=3; p<=n/2; p+=2) {
            if(!prime(p))
                continue;
            if(!prime(n-p))
                continue;
            //printf("%d=%d+%d\n",n,p,q);
            find=1;
            break;
        }
        if(!find)
        {
            puts("Congratulations!");
        }
    }
    long long end=clock();
    printf("%.3f second(s).\n",(end-start)*1e-3);
    return 0;
}
